Mariners vs. Royals prediction: Seattle favored to win Thursday's MLB matchup [9/18/2025]

The Kansas City Royals and Seattle Mariners will meet in MLB action at Kauffman Stadium on Thursday, starting at 2:10PM ET.

Stephen Kolek (5-5, 3.72 ERA) will be the starting pitcher for the Royals, while the Mariners have opted for Luis Castillo (9-8, 3.76 ERA).

Based on updated simulations, Dimers' proven MLB model predicts the Mariners as the most likely winner of today's game.

For further insights into Thursday's matchup, including best bets and picks, visit our interactive Mariners vs. Royals predictions page.

Royals vs. Mariners prediction: Who will win, cover the run line?

Using powerful machine learning and data, we have simulated the result of Thursday's MLB game between the Mariners and Royals 10,000 times as part of our MLB predictions coverage.

Our leading predictive model currently gives the Mariners a 53% chance of beating the Royals.

According to our model, the Royals (+1.5) have a 59% chance of covering the run line, while the over/under total of 9 runs has a 54% chance of going over.

Mariners vs. Royals odds [9/18/2025]

We have researched the best MLB odds in America for this game, which are listed here:

Bet Type	Mariners	Royals
Run Line	-1.5 (+138)	+1.5 (-150)
Moneyline	-119	+105
Total	o9 (-108)	u9 (-102)

All odds are correct at the time of publication and are subject to change.

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Mariners vs. Royals picks and best bets

Our model's biggest edge in today's Mariners vs. Royals matchup is on the run line.

Our expert predictions, aligned with the latest odds, reveal the best MLB picks and MLB best bets for every game throughout the season.

Unlimited access to our full suite of picks, including this one, is available via Dimers Pro.

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Mariners vs. Royals game-day updates and essential details

Thursday's MLB action between the Royals and Mariners at Kauffman Stadium is scheduled to begin at 2:10PM ET.

• Who: Seattle Mariners vs. Kansas City Royals
• Date: Thursday, September 18, 2025
• Time: 2:10PM ET/11:10AM PT
• Venue: Kauffman Stadium

Dimers' comprehensive preview of Thursday's Mariners vs. Royals matchup includes our prediction, picks and the latest betting odds.

Before making any Mariners vs. Royals picks, be sure to check out the latest MLB predictions and betting advice from Dimers Pro.

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Conclusion

We predict the Mariners, with a 53% win probability, will likely beat the Royals on Thursday.

AI and automation have enhanced this article to quickly deliver accurate Mariners vs. Royals insights, with human oversight ensuring high editorial quality. Our predictions are sourced from the latest data to help you make informed decisions. For additional resources and advice on responsible gambling, please call 1-800-GAMBLER.

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